# 6 21 25 triangle

### Obtuse scalene triangle.

Sides: a = 6   b = 21   c = 25

Area: T = 50.99901951359
Perimeter: p = 52
Semiperimeter: s = 26

Angle ∠ A = α = 11.20108183696° = 11°12'3″ = 0.19554911595 rad
Angle ∠ B = β = 42.83334280661° = 42°50' = 0.74875843497 rad
Angle ∠ C = γ = 125.9665753564° = 125°57'57″ = 2.19985171445 rad

Height: ha = 16.9976731712
Height: hb = 4.85662090606
Height: hc = 4.07992156109

Median: ma = 22.89110462845
Median: mb = 14.84108220797
Median: mc = 9.06991785736

Inradius: r = 1.96111613514
Circumradius: R = 15.44441456421

Vertex coordinates: A[25; 0] B[0; 0] C[4.4; 4.07992156109]
Centroid: CG[9.8; 1.3659738537]
Coordinates of the circumscribed circle: U[12.5; -9.07703712501]
Coordinates of the inscribed circle: I[5; 1.96111613514]

Exterior(or external, outer) angles of the triangle:
∠ A' = α' = 168.799918163° = 168°47'57″ = 0.19554911595 rad
∠ B' = β' = 137.1676571934° = 137°10' = 0.74875843497 rad
∠ C' = γ' = 54.03442464357° = 54°2'3″ = 2.19985171445 rad

# How did we calculate this triangle?

Now we know the lengths of all three sides of the triangle and the triangle is uniquely determined. Next we calculate another its characteristics - same procedure as calculation of the triangle from the known three sides SSS. ### 1. The triangle circumference is the sum of the lengths of its three sides ### 2. Semiperimeter of the triangle ### 3. The triangle area using Heron's formula ### 4. Calculate the heights of the triangle from its area. ### 5. Calculation of the inner angles of the triangle using a Law of Cosines ### 6. Inradius ### 7. Circumradius ### 8. Calculation of medians #### Look also our friend's collection of math examples and problems:

See more informations about triangles or more information about solving triangles.